Fresh garlic is loaded with health benefits, but does cooking it destroy them. Find out.

Garlic is one of the most commonly used spices in cooking. Not only does it add an enticing flavor to food, but it has some impressive health benefits. It’s long been known for its heart healthy properties which may be related to its anti-inflammatory properties and its ability to reduce platelet clumping; but it also helps to fight off infection because of its antibacterial and antiviral properties. Fresh garlic cloves may also reduce the risk of some types of cancer – particularly stomach cancer. Unfortunately, when most people add it to their diet it’s usually in the form of cooked garlic which may not have the same health properties as raw garlic cloves. Does cooking fresh garlic destroy its health benefits?

Most of the health benefits of garlic come from the sulfur containing compounds it contains. The most notable is allicin. Allicin is responsible for the anti-bacterial, anti-viral, and anti-fungal properties of garlic and also helps to stomp out cancer cells and reduce their growth. In addition, it helps to prevent formation of cancer causing chemicals in the body. It’s these strong sulfur compounds that linger on the breath after a meal – giving rise to “garlic breath”.

Even though the sulfur compounds may do little for your breath, they’re certainly good for your body. When a garlic clove is crushed, the sulfur compound allicin is released. Once exposed to the air, it starts to lose some of its potency, and when you cook garlic some of the sulfur compounds – particularly allicin – are slowly degraded. If you cook garlic in a microwave, you completely destroy the healthful sulfur components. Crushing the garlic clove releases allicin and makes its active ingredients more available, but cooking fresh garlic causes them to be partially destroyed. On the other hand, garlic is still a good source of flavonoids, selenium, and other sulfur compounds which aren’t destroyed by the cooking process.

Obviously, cooking fresh garlic reduces some of its health benefits – but all is not lost. During the cooking process other intermediate sulfur containing compounds are formed that still have health benefits. It’s primarily the anti-viral and anti-bacterial properties found in allicin that are lost when garlic is cooked. The anti-cancer and heart healthy properties are preserved even after cooking garlic since these benefits come from sulfur compounds other than allicin.

The bottom line? You’ll still get some of the health benefits of garlic even if you only eat cooked garlic – as long as it’s not cooked in a microwave. The anti-cancer benefits and the positive benefits for the heart remain intact, although you lose some of the anti-bacterial and anti-viral properties because of the breakdown of allicin. For the most benefits, eat cooked garlic and a little raw garlic too.

How does heating in a microwave change the nutrients in garlic differently than heating by any other means?

Garlic pieces by themselves are too small to cook in a standard microwave – it would be difficult not to overheat at least parts. But when cooked with something sized to what the microwave is made for would seem to be the same as steaming or being in an oven.

I stumbled on to this site looking around for a source for the claim that microwaving garlic causes it to lose its benefits. I would appreciate a link to a a source or a study mentioned that indicates this so I can look into the claim further.